Gastrointestinal Physiological Changes and Their Relationship to Weight Loss Following the POSE Procedure.

BACKGROUND: Primary Obesity Surgery Endolumenal (POSE) is a novel bariatric endoscopic procedure that has been shown to reduce weight safely through 12 months. The study investigated potential mechanisms of weight loss following POSE. METHODS: Patients with class I-II obesity received transmural plications in the gastric fundus and distal gastric body. Patients were evaluated at baseline and at 2- and 6-month follow-up with gastric-emptying (GE) scintigraphy, a validated test of intake capacity (kcal) and plasma glucose homeostasis hormones/gastrointestinal peptides. Weight was recorded through 15 months. Mean data and 95% CIs are reported. Regression modeling assessed variables that influenced total weight loss (%TWL) and excess weight loss (%EWL). RESULTS: POSE was performed on 18 patients (14 F/4 M); mean age 39 years (34-44), body mass index (BMI, kg/m(2)) 36 (95% CI, 35; 37). At 15 months (n = 15), mean TWL was 19.1 ± 6.6% (15.5; 22.8) and EWL was 63.7 ± 25.1% (49.8; 77.6). At 2 and 6 months (n = 18), intake capacity decreased significantly from 901 (685; 1117) to 473 (345; 600) and 574 kcal (418; 730), respectively (p < 0.001). At 2 months, GE was delayed but returned to baseline levels at 6 months (n = 18). Glucose/insulin ratio improved (p < 0.05). Postprandial decrease in ghrelin was enhanced (p = 0.03) as well as postprandial increase in PYY (p = 0.001). The best model for EWL prediction 15 months after POSE (R (2): 66%, p = 0.006) included pre-POSE BMI, post-POSE GE, and postprandial PYY increase. CONCLUSIONS: The POSE procedure was followed by significant sustained weight loss and improved glucose homeostasis and satiation peptide responses. Weight loss following POSE may be mediated through changes in gastrointestinal neuro-endocrine physiology.

Bajo rendimiento diagnóstico de la PET/TC con 11C-colina en la detección de metástasis hepáticas de origen prostático / Low diagnostic yield of the 11C-choline PET/CT in the detection of liver metastasis from prostate cancer

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Stress and rest myocardial SPET quantification with 201Tl and 99Tcm-tetrofosmin: a comparison.

99Tcm-tetrofosmin is a new myocardial perfusion agent that has excellent physical and pharmacokinetic characteristics for performing tomographic myocardial perfusion studies. The aim of this study was to compare the behaviour of 99Tcm-tetrofosmin and 201Tl in the assessment of ischaemia and viability in patients with previous myocardial infarction. Twenty consecutive patients who had suffered infarction and been referred for assessment of ischaemia and myocardial viability were enrolled into the study. Each patient underwent two stress tests performed no more than 10 days apart, one with a 201Tl exercise-reinjection-redistribution method and one with a 99Tcm-tetrofosmin short protocol (exercise-rest). The results were quantified using polar maps to represent images for stress, rest and reversibility. The post-stress images showed there was a slight tendency to overestimate defect size with 99Tcm-tetrofosmin in the lateral region (P < 0.006). We found no significant differences between the two tracers when comparing reversibility. The same defect size at rest were obtained when the maps for 201Tl with uptake of 50% were compared with those for 99Tcm-tetrofosmin with uptake of 45%. Agreement between the two agents for assessment of viability was 93%. We conclude that the quantitative assessment of myocardial ischaemia and uptake of 99Tcm-tetrofosmin at rest are comparable to those obtained with 201Tl in patients who have suffered myocardial infarction.

[ST segment elevation during exercise test and perfusion scintigraphy in patients without infarction]. / Elevación del segmento ST en la prueba de esfuerzo y gammagrafía de perfusión en pacientes sin infarto.

BACKGROUND: The features of perfusion scintigraphy in patients who show exercise-induced ST-segment elevation in the absence of previous infarction have been assessed in only a few reports. Therefore, we have evaluated our experience in a wide review of exercise 201-thallium scintigraphies. METHODS: 16,620 exercise 201-thallium scintigraphies, carried out between 1986 and 1993, have been retrospectively reviewed. Fourteen patients (0.8/1000) without previous infarction who were evaluated for chest pain showed ST-segment elevation. In all patients coronary arteriography was also available. RESULTS: Five patients were free from significant coronary artery stenoses, 6 had one-vessel disease, 2 had two-vessel disease, and the remaining patient had three-vessel disease. In 8 patients ST-segment elevation (up to 3-24 mm) was inferior, in 5 anterior and in 1 lateral. The radionuclide was injected during ST-segment elevation in 10 cases and before such elevation (which developed in the postexercise phase) in 4. In 3 out of these 4, which had angiographically normal coronary arteries, the scintigraphy was negative. In all cases where thallium-201 was injected during ST elevation, severe perfusion defects were detected corresponding to the localization of ST elevation. In the 4 patients with critical coronary stenoses, thallium-201 redistribution after 3 hours was partial. CONCLUSIONS: In patients without previous infarction and with exercise-induced ST-segment elevation, very severe perfusion defects are detected when the radionuclide has been injected during the crisis. Thallium-201 redistribution after 3 hours was not total in patients with fixed critical stenoses. When radionuclide injection preceded the crisis, the result of the scintigraphy was in agreement with the coronary anatomy.

Relations among intragastric pressure, postcibal perception, and gastric emptying.

Our aims were to investigate, first, the relationship between gastric tone (measured with a barostat) and gastric emptying (measured by radioscintigraphy with and without barostat) and, second, to determine the effect of a symptomatic intragastric pressure increment on gastric emptying. In 16 healthy subjects we quantified simultaneously gastric tone, emptying, and perception at two different intragastric pressure levels: 2 mmHg (low pressure) or 8 mmHg above intra-abdominal pressure (high pressure). At the low intragastric pressure level, ingestion of the meal induced an additional expansion in intragastric volume of 285 +/- 50 ml (P < 0.001), which reflected a gastric accommodative relaxation. At the high pressure level, intragastric volume expanded further, but neither low nor high pressure levels had significant effects on solid emptying. Interestingly, low and high pressure levels produced a similar, modest but significant, acceleration of liquid emptying (17 +/- 5 and 17 +/- 4%, respectively). However, although the low pressure was largely unperceived (score 1.0 +/- 0.5; NS), the high pressure level produced significant symptomatic perception (score 2.5 +/- 0.9; P < 0.05 vs. low pressure). We conclude that 1) gastric accommodation to a meal prevents volume-dependent wall tension increments and 2) the stomach adapts to increments in postcibal intragastric pressure by a limited acceleration of liquid emptying, but wall stress triggers a symptomatic alert mechanism.